Advice which online platform to use to rebuild XLS model [personal website]

I would like some advice: I created a stock portfolio model (in XLS) which I seek to replicate in an online environment. As a preparation I build the model in Python + Pandas and a simplified TKinter GUI. I am quite limited in my time and so I would like to test a setup in a free / low cost online environment where I can slowly learn to rebuild my model with subsequent reporting views and graphs.

My question - if permitted - is if the community has some advice on platforms / languages / etcetera that could get me started. My model has the following main features: - multiple worksheets that contain past trading information (up to 150 mostly calculated colums including data validation), prices (no real time pricing foreseen - only manual input), to be followed strategy - reports: graphs, tables, pivot tables

When the model 'works' it could be released as a real site but for now a free or low cost test platform would suits my limited time I have now. I might even need to hire a real developer at some point but first things first.

Thanks. KR, J.